Comparison of enzyme phenotypes in human bladder tumours and experimentally induced hyperplastic and neoplastic lesions of the rat urinary bladder. A combined histochemical and immunohistochemical approach

The expression of a number of enzymes involved in drug metabolism, membrane function etc. was compared in hyperplastic and neoplastic lesions of the rat bladder and in human bladder tumours. Transitional cell carcinomas (TCC) in both rat and Man were characterized by decreased alkaline phosphatase (ALP) and increased gamma-glutamyl transpeptidase (GGT), beta-glucuronidase (beta-G1), succinate dehydrogenase (SD) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, binding for antibodies specific for different cytochrome P-450 species (UT50, PB3a, MC1, MC2) and microsomal epoxide hydrolase (mEHb) was elevated in both murine and human tumours. Comparison of the enzyme phenotype in hyperplastic lesions induced by freeze ulceration or uracil administration with that in preneoplastic papillary or nodular hyperplasia (PNH) and TCC suggested, however, that most of the alteration in enzyme content or activity was non-specific and related to requirements for epithelial cell proliferation. On the other hand, the decreased ALP, and increased GGT and beta-G1 activity appeared more directly related to neoplastic transformation. The results suggested that qualitative differences exist between reactive hyperplasia and preneoplastic or neoplastic lesions in the urinary bladder. The finding of increased cytochrome P-450, in clear contrast to the reduction characteristic of preneoplastic hepatic lesions, may be important with regard to the observed difference in neoplastic transformation between the bladder and liver in response to drug metabolising enzyme inducers.     

Nicotine enhances neovascularization and promotes tumor growth

Solid tumors require vascularization for their growth. Bone marrow-derived endothelial progenitor cells participate in tumor angiogenesis. Here, we show that nicotine markedly accelerated growth of colon cancer cells inoculated subcutaneously in mice but had no effect on proliferation of carcinoma cells in vitro. We found that the tumor growth was associated with increased vascularization of the tumor and that bone marrow-derived cells contributed to the formation of the new blood vessels. Our findings show that nicotine promotes tumor growth, at least in part, by stimulating tumor-associated neovascularization.     

Tissue distribution of Ca2+-dependent activator protein for secretion family members CAPS1 and CAPS2 in mice.

The family of Ca2+-dependent activator proteins for secretion (CAPS) is involved in dense-core vesicle exocytosis. CAPS1/CADPS1 and CAPS2/CADPS2 have been identified in mammals. CAPS1 regulates catecholamine release from neuroendocrine cells, whereas CAPS2 is involved in the release of brain-derived neurotrophic factor and neurotrophin-3 from cerebellar granule cells. CAPS1 and CAPS2 are predominantly expressed in brain. Here we show the immunohistochemical localization of the CAPS family proteins in various mouse tissues. In the pituitary gland, CAPS1 and CAPS2 were localized to the pars nervosa and the pars intermedia, respectively. In non-neural tissues, CAPS1 was observed in the islets of Langerhans, minor cell types of the spleen and stomach, and medullary cells of the adrenal gland, whereas CAPS2 was present in bronchial epithelial cells, thyroid parafollicular cells, chief cells of the stomach, ductal epithelium of the salivary gland, kidney proximal tubules, and minor cell types of the thymus, spleen, and colon. These results suggest that secretion from distinct cell types in various tissues involves either or both members of the CAPS family.     

Identification of cis-localization elements of the maize 10-kDa δ-zein and their use in targeting RNAs to specific cortical endoplasmic reticulum subdomains

The RNAs for the storage proteins of rice ( Oryza sativa ), prolamines and glutelins, which are stored as inclusions in the lumen of the endoplasmic reticulum (ER) and storage vacuoles, respectively, are targeted by specific cis -localization elements to distinct subdomains of the cortical ER. Glutelin RNA has one or more cis -localization elements (zip codes) at the 3' end of the RNA, whereas prolamine has two cis -elements; one located in the 5' end of the coding sequence and a second residing in the 3'-untranslated region (UTR). We had earlier demonstrated that the RNAs for the maize zeins ('prolamine' class) are localized to the spherical protein body ER (PB-ER) in developing maize endosperm. As the PB-ER localization of the 10-kDa δ-zein RNA is maintained in developing rice seeds, we determined the number and proximate location of their cis -localization elements by expressing GFP fusions containing various zein RNA sequences in transgenic rice and analyzing their spatial distribution on the cortical ER by in situ RT-PCR and confocal microscopy. Four putative cis -localization elements were identified; three in the coding sequences and one in the 3'-UTR. Two of these zip codes are required for restricted localization to the PB-ER. Using RNA targeting determinants we show, by mis-targeting the storage protein RNAs from their normal destination on the cortical ER, that the coded proteins are redirected from their normal site of deposition. Targeting of RNA to distinct cortical ER subdomains may be the underlying basis for the variable use of the ER lumen or storage vacuole as the final storage deposition site of storage proteins among flowering plant species.     

Comparison of enzyme phenotypes in human bladder tumours and experimentally induced hyperplastic and neoplastic lesions of the rat urinary bladder

The expression of a number of enzymes involved in drug metabolism, membrane function etc. was compared in hyperplastic and neoplastic lesions of the rat bladder and in human bladder tumours. Transitional cell carcinomas (TCC) in both rat and Man were characterized by decreased alkaline phosphatase (ALP) and increased gammaglutamyl transpeptidase (GGT), β-glucuronidase (β-Gl), succinate dehydrogenase (SD) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, binding for antibodies specific for different cytochrome P-450 species (UT₅₀, PB_3a, MC₁, MC₂) and microsomal epoxide hydrolase (mEHb) was elevated in both murine and human tumours. Comparison of the enzyme phenotype in hyperplastic lesions induced by freeze ulceration or uracil administration with that in preneoplastic papillary or nodular hyperplasia (PNH) and TCC suggested, however, that most of the alteration in enzyme content or activity was non-specific and related to requirements for epithelial cell proliferation. On the other hand, the decreased ALP, and increased GGT and β - Gl activity appeared more directly related to neoplastic transformation. The results suggested that qualitative differences exist between reactive hyperplasia and preneoplastic or neoplastic lesions in the urinary bladder. The finding of increased cytochrome P-450, in clear contrast to the reduction characteristic of preneoplastic hepatic lesions, may be important with regard to the observed difference in neoplastic transformation between the bladder and liver in response to drug metabolising enzyme inducers. Supported by Grants-in-aid for Cancer Research and a Comprehensive 10 Year Strategy for Cancer Control from the Ministry of Health and Welfare, for Cancer Research and Scientific Research from the Ministry of Education, Science and Culture, and by a grant from the Deutsche Forschungsgemeinschaft     

G-CSF stimulates angiogenesis and promotes tumor growth: potential contribution of bone marrow-derived endothelial progenitor cells

Solid tumors require neovascularization for their growth. Recent evidence indicates that bone marrow-derived endothelial progenitor cells (EPCs) contribute to tumor angiogenesis. We show here that granulocyte colony-stimulating factor (G-CSF) markedly promotes growth of the colon cancer inoculated into the subcutaneous space of mice, whereas G-CSF had no effect on cancer cell proliferation in vitro. The accelerated tumor growth was associated with enhancement of neovascularization in the tumor. We found that bone marrow-derived cells participated in new blood vessel formation in tumor. Our findings suggest that G-CSF may have potential to promote tumor growth, at least in part, by stimulating angiogenesis in which bone marrow-derived EPCs play a role.     

Promoters of Rice Seed Storage Protein Genes Direct Endosperm-Specific Gene Expression in Transgenic Rice

The promoters of genes encoding rice seed storage proteins (glutelin,prolamin, globulin and albumin) were analyzed for their abilityto direct rß-gIucuronidase (GUS) gene expression intransgenic rice plants. All promoters tested could direct endosperm-specificexpression of the GUS reporter gene irrespective of variableactivities and patterns in the endosperm. (Received February 27, 1998; Accepted May 16, 1998)